• Journal of Korean Society for Atmospheric Environment
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• v.28 no.3
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• pp.233-248
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• 2012

The national emission from energy sector accounted for 84.7% of all domestic emissions in 2007. Of the energy-use emissions, the emission from mobile source as one of key categories accounted for 19.4% and further the road transport emission occupied the most dominant portion in the category. The road transport emissions can be estimated on the basis of either the fuel consumed (Tier 1) or the distance travelled by the vehicle types and road types (higher Tiers). The latter approach must be suitable for simultaneously estimating $CO_2$, $CH_4$, and $N_2O$ emissions in local administrative districts. The objective of this study was to estimate 31 municipal GHG emissions from road transportation in Gyeonggi Province, Korea. In 2008, the municipalities were consisted of 2,014 towns expressed as Dong and Ri, the smallest administrative district unit. Since mobile sources are moving across other city and province borders, the emission estimated by fuel sold is in fact impossible to ensure consistency between neighbouring cities and provinces. On the other hand, the emission estimated by distance travelled is also impossible to acquire key activity data such as traffic volume, vehicle type and model, and road type in small towns. To solve the problem, we applied a hierarchical cluster analysis to separate town-by-town road patterns (clusters) based on a priori activity information including traffic volume, population, area, and branch road length obtained from small 151 towns. After identifying 10 road patterns, a rule building expert system was developed by visual basic application (VBA) to assort various unknown road patterns into one of 10 known patterns. The expert system was self-verified with original reference information and then objects in each homogeneous pattern were used to regress traffic volume based on the variables of population, area, and branch road length. The program was then applied to assign all the unknown towns into a known pattern and to automatically estimate traffic volumes by regression equations for each town. Further VKT (vehicle kilometer travelled) for each vehicle type in each town was calculated to be mapped by GIS (geological information system) and road transport emission on the corresponding road section was estimated by multiplying emission factors for each vehicle type. Finally all emissions from local branch roads in Gyeonggi Province could be estimated by summing up emissions from 1,902 towns where road information was registered. As a result of the study, the GHG average emission rate by the branch road transport was 6,101 kilotons of $CO_2$ equivalent per year (kt-$CO_2$ Eq/yr) and the total emissions from both main and branch roads was 24,152 kt-$CO_2$ Eq/yr in Gyeonggi Province. The ratio of branch roads emission to the total was 0.28 in 2008.

• Journal of the Korean Society of Food Science and Nutrition
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• v.38 no.8
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• pp.1042-1049
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• 2009

It has been reported that trans fat (tFA) may have adverse or beneficial effect depending upon the position and number of double bonds. The presence of tFA in human tissues and fluids is related to dietary intake, intestinal absorption, metabolism and storage, exchanges among compartments. This study investigated the effect of breads containing tFA, soybean or rice on postprandial plasma fatty acid and lipid composition. 33 healthy volunteers were divided into 3 groups and fed soybean bread, rice bread or wheat bread groups containing equivalent amounts of tFA (elaidic acid rich, 3.75 g/day), respectively. Postprandial lipid profiles at 0, 1, 2, 3 and 4 hours after a respective meal were studied. Plasma fatty acid was extracted by the method of Folch and methyl ester of fatty and prepared by acid transmethylation and analyzed by Gas Chromatography. Peaks were identified using pure reference compounds and quantified. Postprandial data indicated that consumption of soybean and rice breads with 3.75 g tFA retarded the appearance of C18:1 and C18:2 tFA in plasma lipid compared to that of wheat bread. Futhermore, soybean and rice bread groups showed lower plasma saturated fatty acid levels than wheat bread group. Postprandial TG level was significantly lowered in soybean bread group compared to that of rice and wheat bread groups. These results imply that soybean bread with high dietary fiber content and biologically active substances may inhibit or delay lipid absorption.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.15 no.1
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• pp.35-44
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• 2017

A gamma-ray peak of $^{226}Ra$ (186.2 keV) overlaps with one of $^{235}U$ (185.7 keV) in a gamma-ray spectrometry system. Though reference peaks of $^{235}U$ can be used to correct the peak interference of $^{235}U$ in the analysis of $^{226}Ra$, this requires a complicated calculation process and a high limit of quantitation. On the other hand, evaluating $^{226}Ra$ using the correction constant in the overlapped peak can make a rapid measurement of $^{226}Ra$ without the complicated calculation process as well as overcome the disadvantage in the indirect measurement of $^{214}Bi$, which means the confinement of $^{222}Rn$ gas in a sample container and a time period to recover the secular equilibrium. About 93 samples with 6 species for raw-materials and by-products were prepared to evaluate the activity of $^{226}Ra$ using the correction constant. The results were compared with the activity of $^{214}Bi$, which means the indirect measurement of $^{226}Ra$, to validate the method of the direct measurement of $^{226}Ra$ using the correction constant. The difference between the direct and indirect measurement of $^{226}Ra$ was generally below about ${\pm}20%$. However, in the case of the phospho gypsum, a large error of about 50% was found in the comparison results, which indicates the disequilibrium between $^{238}U$ and $^{226}Ra$ in the materials. Application results of the contribution ratio of $^{226}Ra$ were below about ${\pm}10%$. The direct measurement of $^{226}Ra$ using the correction constant can be an effective method for its rapid measurement of raw materials and by-products because the activity of $^{226}Ra$ can be produced with a simple calculation without the consideration of the integrity of a sample container and the time period to recover the secular equilibrium.

• Journal of the Korean Society for Marine Environment & Energy
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• v.11 no.4
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• pp.181-190
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• 2008

To response climate change and Kyoto protocol and to reduce greenhouse gas emissions, marine geological storage of $CO_2$ is regarded as one of the most promising option. Marine geological storage of $CO_2$ is to capture $CO_2$ from major point sources(eg. power plant), to transport to the storage sites and to store $CO_2$ into the marine geological structure such as deep sea saline aquifer. To design a reliable $CO_2$ marine geological storage system, it is necessary to perform numerical process simulation using thermodynamic equation of state. The purpose of this paper is to compare and analyse the relevant equations of state including ideal, BWRS, PR, PRBM and SRK equation of state. To evaluate the predictive accuracy of the equation of the state, we compared numerical calculation results with reference experimental data. Ideal and SRK equation of state did not predict the density behavior above $29.85^{\circ}C$, 60 bar. Especially, they showed maximum 100% error in supercritical state. BWRS equation of state did not predict the density behavior between $60{\sim}80\;bar$ and near critical temperature. On the other hand, PR and PRBM equation of state showed good predictive capability in supercritical state. Since the thermodynamic conditions of $CO_2$ reservoir sites correspond to supercritical state(above $31.1^{\circ}C$ and 73.9 bar), we conclude that it is recommended to use PR and PRBM equation of state in designing of $CO_2$ marine geological storage process.

• Radiation Oncology Journal
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• v.20 no.4
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• pp.381-390
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• 2002

Purpose : To develop a dose calibration program for the IAEA TRS-277 and AAPM TG-21, based on the air kerma calibration factor (or the cavity-gas calibration factor), as well as for the IAEA TRS-398 and the AAPM TG-51, based on the absorbed dose to water calibration factor, so as to avoid the unwanted error associated with these calculation procedures. Materials and Methods : Currently, the most widely used dosimetry Protocols of high energy photon beams are the air kerma calibration factor based on the IAEA TRS-277 and the AAPM TG-21. However, this has somewhat complex formalism and limitations for the improvement of the accuracy due to uncertainties of the physical quantities. Recently, the IAEA and the AAPM published the absorbed dose to water calibration factor based, on the IAEA TRS-398 and the AAPM TG-51. The formalism and physical parameters were strictly applied to these four dose calibration programs. The tables and graphs of physical data and the information for ion chambers were numericalized for their incorporation into a database. These programs were developed user to be friendly, with the Visual $C^{++}$ language for their ease of use in a Windows environment according to the recommendation of each protocols. Results : The dose calibration programs for the high energy photon beams, developed for the four protocols, allow the input of informations about a dosimetry system, the characteristics of the beam quality, the measurement conditions and dosimetry results, to enable the minimization of any inter-user variations and errors, during the calculation procedure. Also, it was possible to compare the absorbed dose to water data of the four different protocols at a single reference points. Conclusion : Since this program expressed information in numerical and data-based forms for the physical parameter tables, graphs and of the ion chambers, the error associated with the procedures and different user could be solved. It was possible to analyze and compare the major difference for each dosimetry protocol, since the program was designed to be user friendly and to accurately calculate the correction factors and absorbed dose. It is expected that accurate dose calculations in high energy photon beams can be made by the users for selecting and performing the appropriate dosimetry protocol.

• Journal of Food Hygiene and Safety
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• v.33 no.5
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• pp.375-382
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• 2018

This study was conducted to analyze the microbial community and propionic acid production ability of natural microflora in the rice cakes. Genetic analysis of natural microflora in Jorangyi rice cake was performed to select propionic acid - producing bacteria. Selected propionic acid-producing bacteria were cultivated in TSB (tryptic soy broth) supplemented with glucose, and growth characteristics were analyzed by temperature and production of propionic acid was analyzed by gas chromatography (GC-FID). Linearity, detection limit, quantitative limit, and recovery rate were measured to verify propionic acid assay. A total of 98 microbial strains were detected from microflora of Joraengyi rice cake that grew after expiration of shelf life. Lactobacillus casei group accounted for 50.48% and Lactobacillus buchneri was 29.60%. Propionic acid - producing bacteria were Propionibacterium thoenii, P. cyclohexanicum, Propionibacterium_uc, P. jensenii, and P. freudenreichii. Natural bacteria and Lactobacillus spp. did not produce propionic acid during 14 days but P. cyclohexanicum, P. freudenreichii subsp. Shermanii, P. thoenii and P. jesenii produced $263.47{\mu}g/mL$, $338.90{\mu}g/mL$, $325.43{\mu}g/mL$ and $222.17{\mu}g/mL$ during 4 days and 2,462.02 and 2,904.78, 2,220.64, $3,519.17{\mu}g/mL$ during 14 days. As a result of this study, it was affirmed that the natural microflora of Joraengyi rice cake during storage can produce propionic acid from natural sources even if a high concentration of propionic acid is not intentionally added. Because of characteristics of rice cake composed of starch and glucose. This study will be used as a recognition criterion to detect natural preservatives such as propionic acid in starchy foods such as rice cakes and as reference standard safety management data.

• Management & Information Systems Review
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• v.37 no.3
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• pp.27-47
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• 2018

In this study, we examine how land use zoning affects the land price controlling other variables such as road-facing condition of the land, land form, land age after its development and land size. We employ geographically weighted regression analysis which reflects spatial dependency as methodology with a data sample of land transaction price data of Jangyu, a new town, in Korea. The results of our empirical analysis show that the respective coefficients of traditional regression and geographically weighted regression are not significantly different. However, after calculating Moran's Index with residuals of both OLS and GWR models, we find that Moran's Index of GWR decreases around 26% compared to that of OLS model, thus improving the problem of spatial autoregression of residuals considerably. Unlike our expectation, though, in both traditional regression and geographically weighted regression where residential exclusive area is used as a reference variable, the dummy variable of the residential land for both housing and shops shows a negative sign. This may be because the residential land for both housing and shops is usually located in the level area while the residential exclusive area is located at the foot of a mountain or on a gentle hill where the residents can have good quality air and scenery. Although the utility of the residential land for both housing and shops is higher than its counterpart's since it has higher floor area ratio, amenity which can be explained as high quality of air and scenery in this study seems to have higher impact in purchase of land for housing. On the other hand, land for neighbourhood living facility seems to be valued higher than any other land zonings used in this research since it has much higher floor area ratio than the two land zonings above and can have a building with up to 5 stories constructed on it. With regard to road-facing condition, land buyers seem to prefer land which faces a medium-width road as expected. Land facing a wide-width road may have some disadvantage in that it can be exposed to noise and exhaust gas from cars and that entrance may not be easy due to the high speed traffic of the road. In contrast, land facing a narrow road can be free of noise or fume from cars and have privacy protected while it has some inconvenience in that entrance may be blocked by cars parked in both sides of the narrow road. Finally, land age variable shows a negative sign, which means that the price of land declines over time. This may be because decline of the land price of Jangyu was bigger than that of other regions in Gimhae where Jangyu, a new town, also belong, during the global financial crisis of 2008.

• Tuberculosis and Respiratory Diseases
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• v.43 no.2
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• pp.221-227
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• 1996

Background : Measurement of pleural fluid constituents are of value in the diagnosis of pleural effusions and in the seperation of exudates from transudates. The position of the patient(sitting or lying) prior to thoracentesis may result in difference in the measurement of these constituents. The purpose of this study is to determine whether postural differences in pleural fluid constituents exist, and if so, whether they are of any clinical significance. Method : 41 patients with pleural effusions on chest roentgenography were prospectively studied. The fluid cell counts, partial gas tension, and concentrations of chemical constituents were compared in the supine and upright positions. Results : 1) A total of 10 patients were found to have an transudative effusion. In the transudates there was no significant difference in pleural fluid constituents according to posture change. 2) A total of 31 patients were found to have an exudative effusion. Statistically significant postural changes were noted in pH, WBC counts, protein, and LDH concentrations in the exudates. It may be due to postural sedimentary effect in the pleural space. 3) The PCO2 measurements and glucose concentration were not affected by changes in position in exudates or transudates. Conclusion : Postural sedimentary effect occurs in the pleural space with reference to the measurement of certain pleural fluid constituents when an inflammatory process is present. Therefore it is recommended that thoracentesis after 30 minutes in the sitting position should be performed.

• Journal of the Korean Society for Marine Environment & Energy
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• v.13 no.1
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• pp.18-29
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• 2010

Offshore subsurface storage of $CO_2$ is regarded as one of the most promising options to response severe climate change. Marine geological storage of $CO_2$ is to capture $CO_2$ from major point sources, to transport to the storage sites and to store $CO_2$ into the offshore subsurface geological structure such as the depleted gas reservoir and deep sea saline aquifer. Since 2005, we have developed relevant technologies for marine geological storage of $CO_2$. Those technologies include possible storage site surveys and basic designs for $CO_2$ transport and storage processes. To design a reliable $CO_2$ marine geological storage system, we devised a hypothetical scenario and used a numerical simulation tool to study its detailed processes. The process of transport $CO_2$ from the onshore capture sites to the offshore storage sites can be simulated with a thermodynamic equation of state. Before going to main calculation of process design, we compared and analyzed the relevant equation of states. To evaluate the predictive accuracies of the examined equation of states, we compare the results of numerical calculations with experimental reference data. Up to now, process design for this $CO_2$ marine geological storage has been carried out mainly on pure $CO_2$. Unfortunately the captured $CO_2$ mixture contains many impurities such as $N_2$, $O_2$, Ar, $H_{2}O$, $SO_{\chi}$, $H_{2}S$. A small amount of impurities can change the thermodynamic properties and then significantly affect the compression, purification and transport processes. This paper analyzes the major design parameters that are useful for constructing onshore and offshore $CO_2$ transport systems. On the basis of a parametric study of the hypothetical scenario, we suggest relevant variation ranges for the design parameters, particularly the flow rate, diameter, temperature, and pressure.

• Analytical Science and Technology
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• v.26 no.3
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• pp.165-173
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• 2013

To establishment of PT Program for Indoor air quality field that manufacture of confidential development PTMs (proficiency testing materials) and examined of proficiency testing evaluation included sampling process whether or not that is valid. Confirmation of homogeneity and stability of PTMs prepared. PTMs were confirmed to be homogeneous enough to be used as proficiency testing materials since withinbottle homogeneities of the RMs were lower than 0.3 times of targeted standard deviation of proficiency testing. The result of this study showed that the Robust RSD of proficiency testing for VOCs (volatile organic compounds) appeared 23~43% in concentration of 50~320 ${\mu}g/m^3$ for Method A(Distribution by adsorption in Tenax-tube of VOCs), but less 13~42% in concentration of 200~1200 ${\mu}g/m^3$, 16~31% in concentration of 100~450 ${\mu}g/m^3$ for Method B (distribution by VOCs of gas phase in 10L Tedalr bag), C (directly sampling of cylinder with high pressure) respectively. The result of this study showed that method C with sampling is most adequate to the proficiency testing for VOCs in indoor air.